The present invention relates generally to chucks for use with drills or with electric or pneumatic power drivers. More particularly, the present invention relates to a chuck of the keyless type which may be tightened or loosened by hand or by actuation of the driver motor.
Both hand and electric or pneumatic tool drivers are well known. Although twist drills are the most common tools used with such drivers, the tools may also comprise screwdrivers, nut drivers, burrs, mounted grinding stones and other cutting or abrading tools. Since the tools may have shanks of varying diameter or the cross-section of the tool shank may be polygonal, the device is usually provided with a chuck which is adjustable over a relatively wide range. The chuck may be attached to the driver by a threaded or tapered bore.
A wide variety of chucks have been developed in the art. In the simplest form of chuck, three jaws spaced circumferentially approximately 120 degrees apart from each other are constrained by angularly disposed passageways in a body attached onto the drive shaft and configured so that rotation of the body in one direction relative to a constrained nut engaging the jaws forces the jaws into gripping relationship with respect to the cylindrical shank of a tool, while rotation in the opposite direction releases the gripping relationship. Such a chuck may be keyless if it is rotated by hand. One example of such a chuck is disclosed in U. S. Pat. No. 5,125,673 entitled xe2x80x9cNon-Impact Keyless Chuckxe2x80x9d commonly assigned to the present assignee, and whose entire disclosure is incorporated by reference herein.
Despite the success of keyless chucks such as set forth in U.S. Pat. No. 5,125,673, varying configurations of chucks are desirable for a variety of applications. Currently utilized in a variety of chuck applications are ball bearings for reducing friction between the nut and body from axial thrust of the nut onto the body. These bearings are sometimes caged and have separate top and bottom thrust races. Sometimes the body or the nut, if hard enough, can serve as the bottom or top thrust race, respectively. It would be desirable to have a keyless chuck that requires fewer components or lower manufacturing or assembly cost. In addition, it would be desirable to have a chuck configuration whereby radial as well as axial thread stresses were minimized when the chuck was operated. Further, it would be desirable to have a chuck whereby the front sleeve is maintained in place by a nosepiece that is both functional and serves an aesthetic purpose.
The present invention recognizes and addresses the foregoing considerations, and others of prior art constructions and methods.
Accordingly, it is an object of the present invention to provide an improved chuck.
It is another object of the present invention to provide a chuck that minimizes radial as well as axial stress during operation.
It is another object of the present invention to provide a keyless chuck that has a minimum number of individual components that must be assembled.
It is another object of the present invention to provide a chuck with an improved nosepiece that is both decorative and retains the front sleeve in place.
Yet another object of the present invention is to provide an improved mechanism for maintaining a one-piece nut on the body of a chuck.
These and other objects are achieved by providing a chuck for use with a manual or power driver having a rotatable drive shaft, the chuck comprising a generally cylindrical body member having a nose section and a tail section. The tail section has an axial bore formed therein to mate with the drive shaft of the driver, and the nose section has an axial bore formed therein and a plurality of angularly disposed passageways formed therethrough and intersecting the axial bore. The chuck further includes a plurality of jaws slidably positioned in each of the angularly disposed passageways, each of the jaws having a jaw face formed on one side thereof and threads formed on the opposite side thereof. The chuck further includes a nut rotatably mounted on the body and in engagement with the threads of the jaws and a bearing thrust ring fixed on the body member. The chuck further includes a self-contained anti-friction bearing assembly disposed between the nut and the thrust ring and a generally cylindrical front sleeve member in driving engagement with the nut and overlying the nose section of the body member whereby when the front sleeve member is rotated with respect to the body member, the jaws will be moved thereby.
These and other objects are also accomplished by providing a chuck for use with a manual or power driver having a rotatable drive shaft, the chuck comprising a generally cylindrical body member having a nose section and a tail section, the tail section having an axial bore formed therein to mate with the drive shaft of the driver, and the nose section having an axial bore formed therein and a plurality of angularly disposed passageways formed therethrough and intersecting the axial bore. The chuck further includes a plurality of jaws slidably positioned in each of the angularly disposed passageways, each of the jaws having a jaw face formed on one side thereof and threads formed on the opposite side thereof. The chuck further includes a nut rotatably mounted on the body and in engagement with the threads on the jaws, and a generally cylindrical front sleeve member overlying the nose section of the body member and in driving engagement with the nut. The chuck further includes a rust-resistant nosepiece adapted to be secured to the nose section of the body, the nosepiece maintaining the front sleeve member in driving engagement with the nut, whereby when said front sleeve member is rotated with respect to the body member, the jaws will be moved thereby.
These and other objects are further accomplished by providing a chuck for use with a manual or powered driver having a rotatable drive shaft, the chuck comprising a generally cylindrical body member having a nose section and a tail section. The tail section is adapted to mate with the drive shaft of the driver and the nose section having an axial bore formed therein and a plurality of angularly disposed passageways formed therethrough and intersecting said axial bore. The chuck further includes a plurality of jaws slidably positioned in the angularly disposed passageways, each of the jaws having a jaw face formed on one side thereof. The chuck further including a nut rotatably mounted on the body member and in engagement with the threads on the jaws. The chuck further includes a nut retainer member received on the body for maintaining the nut on the body, the nut retainer member including a frusto-conical portion. The chuck further includes a generally cylindrical front sleeve member in driving engagement with the nut and overlying the nose section of the body member whereby when the front sleeve member is rotated with respect to the body member, the jaws will be moved thereby. In a preferred embodiment, the nut retainer member further includes a cylindrical portion which is press fitted onto the body member.
Other objects, features and aspects of the present invention are discussed in greater detail below.